During the past year, our research included: (1) studies of etiological mechanisms (i.e., genetic and environmental influences) on low CSF 5-HIAA concentrations and alcohol consumption; (2) studies of behaviors associated with individual differences in alcohol consumption in rhesus monkeys selectively bred for target CSF 5-HIAA concentrations; (3) investigations of variables that affect alcohol consumption (e.g., whether the capacity to binge or sip an alcohol solution affects rates of consumption in impulsive monkeys); (4) pharmacological treatment of aggression and alcohol consumption using tryptophan and serotonin reuptake inhibitors; (5) tryptophan treatment of self-injurious behavior; (6) investigations of the role that taste plays in excessive consumption and whether an affinity for reinforcing agents such as sugar solutions are positively correlated with high alcohol consumption; (7) studies of sleep and activity in subjects with low CSF 5-HIAA; (8) studies of effect of rearing on fear and anxiety, the acquisition of social dominance and subsequent adult maternal behavior; (9) development of new technologies to study chronic alcohol consumption. (10) In collaboration with Dr. Woods, studies were initiated that investigate the role that gustatory factors play in alcohol consumption. He also began to investigate whether high alcohol consumption is correlated with excessive intake of opiates. (11) A collaboration was initiated with Drs. Salem and Hibbeln (LMBB) to investigate the role of essential fatty acids in CNS serotonin functioning. As a corollary of this investigation, a laboratory-wide assessment of cholesterol and essential fatty acids were made to correlate with CSF 5-HIAA concentrations.